sh run...

hit it wendell...

As in all CCIE exams, you should expect that the easiest or most direct ways to a solution might be unavailable to you. In troubleshooting, perhaps the easiest way to the source of most problems is through the show run command or variations on it. Therefore, we’ll institute a simple “no show run” rule in this section that will force you to use your knowledge of more in-depth troubleshooting commands in the Cisco IOS portion of this section.

and he's right...

sh run is for pussy's...

subinterface boogers...

when a subinterface is created there are boogers left behind, but they don't show up in show run or show start, they only show up when you show run interface;

r2620_03(config)#int fa0/0.1
r2620_03(config-subif)#encap dot1q 100
r2620_03(config-subif)#do sh run int fa0/0.1
Building configuration...

Current configuration : 60 bytes
!
interface FastEthernet0/0.1
 encapsulation dot1Q 100
end

r2620_03(config-subif)#exit
r2620_03(config)#no int fa0/0.1
% Not all config may be removed and may reappear after reactivating the sub-inte
rface

r2620_03(config)#do sh run int fa0/0.1
Building configuration...

Current configuration : 5 bytes
end
(this means my current configuration bytes)

r2620_03(config)#

i have subinterface boogers and ether crickets on me...